Vulkan is a low-level cross-platform graphic API broadly supported. There are several projects to implement all other the existing graphic and compute API’s like OpenGL, OpenGL ES, OpenCL, WebGL, DirectX and even Glide on top of Vulkan. Some projects translate Vulkan to other API’s in case there is no native support available due to restrictions of the operating system or not yet available drivers.
The implementation of all the other graphic and compute API’s on top of Vulkan greatly improves compatibility and reduces development efforts of hardware drivers that got more and more complex with the legacy API’s. This unification on one hardware driver reduces development efforts and bugs. The perfect example is RADV for AMD GPU’s, basically just 2 developers implemented a new driver in one year. Vulkan is the right approach to unify the other API’s for the first time successfully. One improvement in the Vulkan stack will benefit all the implementations on top of it.
Vulkan target
- DirectDraw -> Vulkan
- DD1..DD7 -> D3D9
- see DXWrapper, it is wrapping DirectDraw 1 to 6 calls into DirectDraw 7 and then to Direct3D 9 (using Dd7to9)
- Info: DD8 or greater doesn’t exist, this separate 2D graphic library has been integrated into Direct3D 8
- DD1..DD7 -> D3D9
- Direct3D -> Vulkan
- D3D1,D3D2a,D3D3b,D3D5.2,D3D6.1a -> D3D7
- DXWrapper (license BSD, https://github.com/elishacloud/dxwrapper) is wrapping Direct3D 1 until Direct3D 6 calls into Direct3D 7.
- dgVoodoo2 see D3D8.
- Info: D3D4 has never been released
- D3D7
- dgVoodoo2 see D3D8. Besides dgVoodoo2 there is no other project to translate D3D7 e.g. to D3D8, D3D9 or D3D10.
- no open source Vulkan translation available
- D3D8
- DXWrapper includes D3D8to9 (license BSD, https://github.com/crosire/d3d8to9) which is converting Direct3D 8 to Direct3D 9. It can be used together with D9VK. Additionally DXWrapper can convert DirectInput 1-7 to 8 (requires no further translation as it is input only).
- dgVoodoo2 (license proprietary but free of charge, http://www.dege.freeweb.hu) translates Direct3D 1-7 plus Direct3D 8.1 to DirextX 10.1. This allows the combination with DXVK. Would be nice if GOG would support to release this as open source!
- See GalliumNine, it has a D3D8 to D3D9 codepath
- D3D9
- DXVK (see below, previously DXVK)
- GalliumNine+Zink (refer to OpenGL below). Zink (see below) is available in Mesa for testing and it can be used together with GalliumNine to provide D3D9 support via Gallium3D on Vulkan. NIR was enabled in Mesa 19.1. GalliumNine is based on Gallium3D and provides for Direct3D 9 native API’s for Wine directly.
- D3D9+D3D10+D3D11
- DXVK (license zlib, https://github.com/doitsujin/dxvk) translates DX9, DX10 and DX11 to Vulkan and it works extremly well on Proton (Steam Play) and Wine in Linux. DXVK is almost feature complete. Follow this guide to get DXVK up and running in Wine or just use Steam Play (Proton).
- D3D12
- VKD3D (license LGPL, https://source.winehq.org/git/vkd3d.git) is a Wine project and maps Direct3D 12 directly to Vulkan. There are only a few real D3D12 exclusive titles and usually D3D11 is faster and better supported if available in a game. Though as Direct3D 12 borrowed a lot of concepts from Vulkan and its predecessor Mantle, it’s much less complex compared to Direct3D 11. VKD3D is kept separately so that other developers can use it and the DXVK main developer supports now the development. On proprietary Apple platforms VKD3D supports the use of MoltenVK (see below) to translate from Vulkan further to proprietary Metal.
- D3D1,D3D2a,D3D3b,D3D5.2,D3D6.1a -> D3D7
- OpenGL -> Vulkan
- ZINK (license MIT, https://gitlab.freedesktop.org/mesa/mesa) implements OpenGL translation to Vulkan via Gallium3D API calls in Mesa based on NIR. It was merged to Mesa in October 2019 and is available since Mesa 19.3. Zink supports OpenGL 2.1 and OpenGL ES 1.1/2.0. OpenGL 3.0 is in development.
- OpenGL ES/WebGL -> Vulkan
- ZINK (refer to OpenGL above)
- ANGLE (license BSD, https://github.com/google/angle) is a cross platform project developed by Google. The project describes itself as “ANGLE currently provides translation from OpenGL ES 2.0/3.0 to desktop OpenGL, OpenGL ES, Direct3D 9, Direct3D 11 and Vulkan. Support to translate OpenGL ES 2.0 to Vulkan is available in Android Q, OpenGL ES 3.0 and 3.1 is in development, 3.2 is planned. This project is interesting as it allows at least Android, Linux and Windows to translate OpenGL ES to Vulkan. With this the GPU hardware vendor for Android would only need to supply a Vulkan driver and not anymore the more complex OpenGL ES driver. Another user of ANGLE is hardware acceleration in Chromium and Firefox (with the Webrender engine written in Rust to translate OpenGL ES if not available directly to D3D11) on Windows, so even here Vulkan could be great to unify all drivers.
- OpenCL -> Vulkan
- CLVK (license Apache 2.0, https://github.com/kpet/clvk) implements OpenCL 1.2 on top of Vulkan with the usage of the CLSPV compiler. The first applications like Darktable and Blender do work already with CLVK https://github.com/kpet/clvk/blob/master/docs/supported-applications.md.
- CLSPV (license Apache 2.0, https://github.com/google/clspv) is a prototype compiler for a subset of OpenCL C 1.2 to Vulkan compute shaders. This could be interesting as most of the OpenCL efforts of Intel/AMD struggled in the past (like beignet, rocM), Nvidia is denying any standard with their proprietary Cuda API.
- CLVK (license Apache 2.0, https://github.com/kpet/clvk) implements OpenCL 1.2 on top of Vulkan with the usage of the CLSPV compiler. The first applications like Darktable and Blender do work already with CLVK https://github.com/kpet/clvk/blob/master/docs/supported-applications.md.
- Glide -> Vulkan
- nGlide (license proprietary but free of charge, http://www.zeus-software.com/downloads/nglide) supports the translation from the old Glide graphic API (created by 3Dfx) to Vulkan since version 2.00, read http://www.zeus-software.com/forum/viewtopic.php?f=2&t=2044.
- dgVoodoo2 see DX8 to DX11. Additionally it translates Glide 2.11, 2.45, 3.1 and 3.1 Napalm to DX11. By this it can be used together with DXVK.
Vulkan base
- Vulkan -> CPU fallback (without GPU)
- Kazan (formerly Vulkan-CPU, license LGPLv2.1, https://salsa.debian.org/Kazan-team/kazan) is a Vulkan driver for Linux that runs on top of a regular CPU in case a GPU Vulkan driver is missing like for nouveau where no open source driver is available or in a virtual machine. Instead of C++ the new Kazan is rewritten in Rust. Use cases are computing tasks, Vulkan desktops where no open source Vulkan driver is available, testing a vendor neutral implementation and virtual machines/clouds without a real GPU.
- SwiftShader (license Apache 2.0, https://github.com/google/swiftshader) offers a cross platform Vulkan 1.1 on CPU backend (previously based on OpenGL ES and Direct3D 9) similiar to LLVM for OpenGL. Combined with ANGLE it could allow other API’s like OpenGL ES to run as well on the CPU. SwiftShader can be seen as well like a fallback driver in case the GPU driver doesn’t work or for testing, it is used by Android, Chrome and Firefox (not yet enabled).
- Vulkan -> Vulkan/DX12/Metal/OpenGL ES
- gfx-rs (license Apache 2.0, https://github.com/gfx-rs/gfx) is a Mozilla effort to develop a graphics/hardware abstraction layer written in Rust. The gfx-hal (https://github.com/gfx-rs/portability) is a hardware abstraction layer based on the Vulkan-ic to translate to native backends on Vulkan and additionally to DX12, Metal and OpenGL ES (OpenGL, WebGL). Mozilla is using this for the WebGPU-servo project to use Vulkan for the Web (https://github.com/gfx-rs/wgpu). So besides Firefox becoming a user of gfx-rs they collaborate as well with Dolphin and RPCS3 to improve MacOS support https://gfx-rs.github.io/2018/09/03/rpcs3-dolphin.html.
- Vulkan -> Metal
- MoltenVK (license Apache 2.0, https://github.com/KhronosGroup/MoltenVK, https://moltengl.com/moltenvk) provides Vulkan 1.2 via a translation to Metal for proprietary Apple platforms. This effort is only necessary as Apple refuses and blocks Vulkan support, which is sad for everyone developing platform independent. Thanks to Valve MoltenVK is now open sourced (https://www.phoronix.com/scan.php?page=article&item=vulkan-on-mac&num=1).
- See gfx-rs
- Vulkan -> DX12
- See gfx-rs
- Vulkan -> WebVK/WebGPU -> Vulkan, DX12, Metal
- WebGPU (license MPL2.0, https://github.com/gfx-rs/wgpu) merges common API overlaps of Vulkan, Direct3D 12 (D3D12) and Metal in a new “WebGPU” version http://www.tomshardware.com/news/khronos-meta-api-vulkan-metal-directx12,33962.html or https://gfx-rs.github.io/2019/03/06/wgpu.html. Another alternative is provided by Google with Dawn https://dawn.googlesource.com/dawn. WebGPU offers backends for Vulkan, DX12 and Metal and it will run additionally in web browsers. This efforts seems to be required only because Apple refused to allow and implement Vulkan for supporting their proprietary Metal API only for MacOSX and iOS and Microsoft did the same for the Xbox console with DX12. For Linux itself this effort is important, Vulkan is a platform independent solution and this will payout in the long run.
Harmonization
SPIR-V
SPIR-V is a platform independent intermediate language layer for OpenCL and GLSL that is supported by Vulkan. It will be extended to NIR by the nouveau developers.
NIR
The intermediate representation NIR is becoming the common foundation of the Mesa Gallium3D drivers and it allows the Vulkan developments to share more code (paths) with OpenGL and OpenCL. Originally NIR was developed by Intel for their OpenGL mesa driver, later support for the Intel ANV Vulkan driver was added. NIR provided as well the groundwork for the community Vulkan driver RADV for AMD GPU’s.
NIR Status
- OpenGL
- Intel: standard in the Gallium3D Iris driver (Mesa 19.1) and in i915
- AMD: standard in the Gallium3D RadeonSI (before Mesa 20.0 it requires radeonsi_enable_nir=true, required for OpenGL4.6, TGSI will be removed in Mesa 20.0).
- Nouveau: testing since Mesa 19.1 (requires parameter NV50_PROG_USE_NIR=1, https://www.phoronix.com/scan.php?page=news_item&px=Nouveau-NIR-IR-V6), required for OpenGL 4.6.
- Vivante: testing in Etnaviv since Mesa 19.2 (requires parameter ETNA_MESA_DEBUG=nir, https://www.phoronix.com/scan.php?page=news_item&px=Etnaviv-NIR-Compiler-Mesa-19.2)
- VC4/Freedreno: Gallium3D, required for OpenGL 4.6 (https://www.phoronix.com/scan.php?page=news_item&px=Freedreno-OpenCL-SPIR-V-Too)
- VC5/VC6: In development via V3D
- Mali: In development, but not as a Gallium3D driver ( https://www.phoronix.com/scan.php?page=news_item&px=Chai-ARM-Midgard-To-NIR)
- LLVMpipe software fallback Gallium3D: standard (before Mesa 20.0 it requires LP_DEBUG=nir)
- Vulkan
- Intel: standard in ANV
- RadeonSI: standard in RADV
- Zink: standard in Gallium3D for Zink
- Nouveau: not started
- Vivante: not started
- VC4/Freedreno: rpi-vulkan-driver, early stages (https://github.com/Yours3lf/rpi-vulkan-driver/commits/master), but Vulkan support might be limited due to OpenGL ES 2.1 limits (https://www.phoronix.com/scan.php?page=news_item&px=Raspberry-Pi-Vulkan-Code-Drop)
- VC5/VC6: standard in TURNIP (Mesa 19.1)
- OpenCL
- Intel: Beignet offers an alternative OpenCL approach
- RadeonSI: In development via Gallium3D “Clover” (OpenCL 1.2, SPIR-V support since 19.0, https://www.phoronix.com/scan.php?page=news_item&px=SPIR-V-Clover-OpenCL-2018). If the driver doesn’t support SPIR-V yet, this can be translated back to NIR and then it would work on VC5/VC6, Etnaviv or LLVM R too. ROCm is used now for OpenCL on AMD GPU’s instead with its own implementation
- Nouveau: almost finished, patches for Mesa 19.2 ( https://www.phoronix.com/scan.php?page=news_item&px=Nouveau-NIR-V2)
- VC4/Freedreno: development
- VC5/VC6: –
- LLVM software fallback driver offers now OpenCL support after Nir has been enabled (LP_DEBUG=cl)
- DX9
- GalliumNine added NIR support with Mesa 19.1 so that it can be used together with the new Intel Iris Gallium3D driver and with Zink.
HLSL
Glslang could convert HLSL as well to SPIR-V, but not at the same time with the output to DXIL and SPIR-V. Microsoft open sourced in 2017 the Direct X shader compiler DXC for HLSL (high level shading compiler) based on LLVM/Clang. Orginally it did output only DXIL for Windows 10, but Google added in June 2018 a SPIR-V output, which in turn can be used by Vulkan, OpenGL 4.6 and OpenCL (https://github.com/google/DirectXShaderCompiler/tree/linux).
Shader Conductor
Shader Conductor (license MIT, https://github.com/Microsoft/ShaderConductor) is a new project from Microsoft. Besides the DXIL output the Direct X shader compiler can provide as well SPIR-V. SPIR-V could then output to Vulkan or to OpenGL via SPIRV-Cross. Besides this SPIRV-Cross allows as well to go again OpenGL (via GLSL), OpenGL ES (via ESSL), D3d 9/10/11 (via MSL) or to Metal (via MSL), for more details read https://www.phoronix.com/scan.php?page=news_item&px=Microsoft-Shader-Conductor.
Legacy Projects
- GLOVE (license LGPLv3, https://github.com/Think-Silicon/GLOVE) is a open source project (2018-08-01) that is able to translate OpenGL ES 2.0 and EGL 1.4 to Vulkan, with support for Linux (actually limited to X11/XCB without Wayland support), Android and Windows. Think Silicon will extend the support to OpenGL ES 3.2 and OpenGL as well, but there is no OpenGL support so far. Developers wanting to extend Glove can find helpful information here https://github.com/Think-Silicon/GLOVE/blob/master/Docs/GLOVEDesignDocument.md. Requires a CLA to contribute and development stopped almost completly.
- DXUP (license MIT, https://github.com/Joshua-Ashton/dxup) started as a project (2018-04-25) to implement a Direct3D 10 to Direct3D 11 translation layer, and by this it would allow to run via DXVK. But as DXVK got it’s own D3D10 implementation, DXUP had now a separate D3D9-dev branch https://github.com/Joshua-Ashton/dxup/tree/d3d9-dev and it got replaced now by D9VK.
- VK9 (https://github.com/disks86/VK9) runs Direct3D 9 (DX9) on top of Vulkan. It is a wrapper and some demos and some games might run already like Unreal Tournament 1999 (UT99). The project reached milestone 29 at UT99 runs now without major graphical glitches https://techtinker.blogspot.com/2018/12/vk9-has-reached-its-29th-milestone.html. A roadmap can be found here https://github.com/disks86/VK9/wiki/Roadmap. The main developer of VK9 takes a break from this project, so not much progress is expected in the next time.
- VKGL (license MIT, https://github.com/kbiElude/VKGL) is a new project (2018-08-04) with the aim to run Doom 3 in OpenGL 3.2 core profile context on Vulkan as a user translation library. But no goal to extend and it doesn’t work so far.
- GLO (https://github.com/g-truc/glo) is a platform independent project to run OpenGL on top of Vulkan in very early stages and that stagnated. They don’t try to use Mesa Gallium3D code and started from scratch. For more details read https://www.phoronix.com/scan.php?page=news_item&px=OpenGL-Overload-Vulkan.
- D3D9to11 (license LGPLv3, https://github.com/GabrielMajeri/d3d9-to-11) converts DX9 to DX11 which can then be run on Vulkan via DXVK. The project started as code merge proposal to the original DXVK project (2018-08-09, https://github.com/GabrielMajeri/dxvk/tree/d3d9), but as it is off target, it will live now in a separate branch and by this it will continue to use a lot of the groundwork of DXVK. No activity in September and October, discontinued in November 2018.
- VulkanOnD3D12 (license Apache, https://github.com/Chabloom/VulkanOnD3D12) translates native Vulkan into DX12. This might be helpful only for XBox as Microsoft refuses and disallows Vulkan on this platform. On Windows itself Vulkan drivers are available from the Hardware vendors and this effort is just an academic one. No developments in several months.
- Rostkatze (license Apache 2.0, https://github.com/msiglreith/rostkatze) is another Vulkan to DX12 implementation, for more details read https://www.phoronix.com/scan.php?page=news_item&px=Rostkatze-Vulkan-D3D12. No developments in several months.
